Metagenomics offers a new look by accessing the as-yet-unculturable microorganisms that represent the majority of life in soil. Metagenomic analysis of soil is challenging because soil is such a complex environment, containing diverse organisms in a dynamic matrix. The biological, chemical, and physical properties of soil all contribute to the technical difficulties of the analysis, and thus numerous obstacles to cloning and analyzing the metagenome of soil remain to be overcome. Discovery of metabolic networks and small molecules from the cultured microorganisms from soil has been unparalleled in any other environment, and therefore it is likely that the potential for discovery from the uncultured community is similarly enormous. Because most of the uncultured life forms in soil appear to be new species and many represent new genera, there is much to learn about the fundamental functioning of soil microbial communities, and these communities have already yielded new enzymes and antibiotics. Technical advances in DNA recovery, gene expression, and functional analysis will enhance the rate of discovery and make possible productive prospecting of soil for the medicinal, agricultural, and industrial chemicals.